Staff Writer

Peregrine Pharmaceuticals Inc. reported another positive study of its lead product bavituximab in breast cancer patients, with half of the study patients achieving tumor response after two treatment cycles.

Currently, bavituximab is in two separate Phase II combination therapy trials for the treatment of advanced breast cancer. It also is in a Phase II combination trial for the treatment of non-small-cell lung cancer. Those latest results reinforce the positive early data reported last week in the lung cancer trial, the company said.

All three studies have reported positive early results, each of them achieving the pre-stated goal of an objective tumor response, according to Tustin, Calif.-based Peregrine.

The latest results are from a 15-patient trial evaluating bavituximab in combination with chemotherapy drugs carboplatin and paclitaxel in locally advanced or metastatic breast cancer patients. Of the 15 study patients, 14 were deemed evaluable for tumor response.

Seven patients achieved an objective response by about the eight-week mark, after completing two treatment cycles. Six study patients achieved partial tumor responses, and one patient achieved a complete tumor response.

Tumor response was defined as a 30 percent or more reduction in the measurable tumor and no new lesions, based on standard universal criteria. A complete response was defined as no detection of lesions.

Peregrine's other breast cancer trial evaluating the combination of bavituximab and docetaxel also met its primary endpoint, and as a result, that trial expanded enrollment that began last fall.

Now that the second Phase II breast cancer trial has achieved its primary endpoint, it now can be expanded to enroll an additional 31 study patients. Expanded enrollment in the lung cancer trial also is expected to begin ramping up.

Because the ongoing Phase II studies of bavituximab are open-label trials, Peregrine is able to evaluate data as they become available. Steven King, president and CEO, said the goal is to make additional data available around the time of the annual meeting of the American Society of Clinical Oncology (ASCO) May 29-June 2 in Orlando, Fla.

Various updates on the trial data could extend from around the time of ASCO possibly through the end of the year, King said.

Although Peregrine has not yet given any firm projections on its cash runway, King said that the company has enough cash on hand to complete the studies that are ongoing. He said the company has a Department of Defense contract and a manufacturing subsidiary that provide sources of revenue, and it also recently took out a term loan.

But to launch a large Phase III program, King said, the company would like to secure a partner, and talks are ongoing with some of the larger pharmaceutical companies, he said.

The expanded breast cancer trial is being conducted in India, but U.S. centers would be considered as later-stage trials are planned, said Joseph Shan, executive director of clinical and regulatory affairs at Peregrine.

Bavituximab, a monoclonal antibody, targets blood vessels of tumors as opposed to a binding site on a specific type of cancer cell. While Avastin inhibits new vessel growth inside the tumor, Peregrine's product candidate is aimed at the existing blood vessels and could be used alongside other cancer therapies.

Peregrine also is studying bavituximab as a standalone therapy in a Phase I trial in advanced solid cancers. That same compound also is in early stage study for hepatitis C infection. The company's other drug candidate, Cotara, is in a Phase II study in brain cancer.

Shares in Peregrine (NASDAQ:PPHM) closed unchanged at 44 cents.